MIF, iNOS and MHC class II expression in macrophages of lymph nodes of the dogs with visceral leishmaniasis

Abstract

Visceral Leishmaniasis (VL) is a zoonotic disease that has been gained attention lately due to increased dissemination in several regions of Brazil, with a minor expression in the southern region, which may be attributed to cold climate conditions which are less favorable for the vector surviving. Urban areas have been described as locations of higher incidence of the disease in both humans and dogs, proving that the disease is not exclusively encountered in rural zones or in the vicinity of forests. Social problems such as poverty increasing and the lack of sanitation, coupled with the migration of phlebotominic vector from the wild environment to urban zones, favored the occurrence of the epidemia. In southeastern region of Brazil, VL was first diagnosed in 1998, in Araçatuba (SP). Iyt is spreading to the west-center region of the country. Dogs are the main domestic reservoir of the protozoa Leishmania (Leishmania) chagasi, favoring the contamination of the Lutzomyia longipalpis vector, which consequently brings the infection to humans. For this reason, euthanasia of serum-positive dogs is performed. The observation of disease evolution in such conditions is impaired. Therefore, researches that focus to immune-response of the dog against the Leishmania sp. are necessary to elucidate the pathogeny of the disease. This study aims to evaluate the macrophages capability in destroying intracytoplasmic amastigotes forms of L. chagasi, and antigens processing and presentation to T lymphocytes in lymph nodes of naturally infected dogs. The analysis will be accomplished by means of identification of iNOS, MHC-II and MIF antigens by immunohistochemistry technical. (AU)